Spark-indicator.



F. W.BRANDOW.

SPARK INDICATOR.

APPLICATION FILED AUG. 5, 1907.

` Patented Juy 6, 1909.

Fig. 1

8B /NVE/YTOR TTR/VEK UNITED sTATEs rTENT oEErcE.

FRANK WARNER BRANDOW, OF PITTSFIELD, MASSACHUSETTS, ASSIGNOR TO JACOBSON- BRANDOW-COMPANY, OF PIATTSFIELD, MASSACHUSETTS, A CORPORATION OF MASSA- OHUSETTS.

SPARK-INDICATOR.

ne.l cedere.

Specification of Letters Patent.

Patented July 6,1909.

Application led August 54, 1907. Serial No. 387,056.

lTo all whom it may concern:

Be it known that I FRANKXVARNER BRAN- now, a citizen of .the United States, residing at Pittsfield, in the county of Berkshire and State of Massachusetts, have invented certain new and useful Im )rovernents in Electric-Oircuit ,Devices to e Designated as a Sparkelndicator, of which the following is a specification.

rlfhis invention relatesto devices adapted to form part of an electric circuit, employed to ignite a combustible charge operating a motor engine, and to determine the operative conditionv .'of suoli circuit.

One ob] ect of my invention 1s to provide a comparatively simple and inexpensive de vice adapted to form part of an electric circuit for the purpose described which may be easily attached to or detached therefrom and which shall visibly indicate the strength and fre uency of sparks emitted by the current wit the engine and the operative efficiency of the several parts forming,the completed circuit without necessitating theirremoval. And a further object is to enable the operator Ato thereby readily retime the ignition, when that is necessary, without removing any part of the engine, and with these andother ob jects in view my invention consists in certain features ofv construction and arrangement of parts as hereinafter described and clainnad,A

reference being had to the drawings, forming a part of this specification', in which corre- .sponding partsare designated by similar reference c aracters in each of the views.

Referring to the drawings, Figure lis a erspective side view illustrating a preferred crm of my device operatively attached to parts4 of an electric circuit of the character described; F ig. 2 a vertical longitudinal sec'- tion of my device on an enlarged scale; Fig. 3, a detailed bottom view of the base; Fig` 4, an 'end view, of the casing, B4, with the flange. thereon; the inclosed stem being f shown in cross-section; Fig. 5, a sectional view ofy my device attached to a sparleplug of modified construction; Fig. 6, a side view of a section of my device, showing a modified construction of the sliding stem, B3; Figs. 3, 4 and 6 also. being on an enlarged scale.4

Referring to the drawings by letters and numerals, B represents a baseof fiber, or other suitable insulation, provided at either end thereof with metallic-conductors forming parts of an electric circuit and respectively adapted to be readily attached to or detached from the same, and further adapted 'to be electrically connected or disconnected relatively to each other.

B5 is a stud rigidly mounted upon one end of theV base and constructed to support in stationary position over the same and parallel thereto a'cylindrical casing or tube, B4. Said casing is adapted to support a sliding stem, B?, having free longitudinal androtatory movements therein, and a cooperative helical spring, B9. Said stem is provided at its outwardly directed end with a manipulative button -or retractor, B, of ber or other suitable insulation, and at its inwardly trally of the stem, approximate the other ondof the casing and within the same. Y B13 represents an inwardly projected flange of the casing .provided with a notcht B,

therein in the line of movement of stop pins, B7, of sufficient size to allow th ir passage therethrough.

B15 denotes a metall-ic plate held in position against the underside of the base by the riveted end, BS, of the stud and preferably provided laterally with side-clips or clamping arms, B18, and a depending perforated terminal, B1, separately provided with like clips or arms. Said clamping-arms, Blsfare adapted to hold in position a cable, C, containing a feed-wire, C', secured to the terminal; B1,

by the clamping-arms respectively provided 4 thereon. Bl represents a clamp rigidly secured to the top of the opposite end of the base preferably` by means of a hollowr1vet, B17, passed transversely through said parts and an intermediate metallic plate, B20,

Similar to plate Bls'aid rivet being providedy with a socket or recess, Bl, in the bottom thereof.

Said clamp is preferably con-. structed of a resilient metallic str1p havingto the particular ypreventing the 'closing of the circuit.

is further provided with a free vend raised substantially perpendicular to the base soasto form a terminal, B2, in contact with the spark point B12.

In Fig. 6 a modified construction of an adjustable electrode is illustrated in which the sliding-stem., B3, is provided with ascrew thread in substitution for vstop-pins, B7,-

wliile the flange on the casing, B, is accordingly provided with a-sciew threaded edge to engage therewith.

It may readily be seen-that other a proved forms of sparleplugsmay be adopte for use in connection with my device in preference construction heretofore described.` An illustration of such other form is shown in F ig. 5. In this instance afhead, A1, is provided with a screw-threaded stem, A3, projected through the slotted clamp, B1, the hollow rivet, B17, and intermediate parts,

while a knurl-nut, A2, engaging with the stem, A3, secures the `parte iirmly together in electrical connection.,

The operation lof my device may bedescribed as follows: When forming a par of completed circuit my device is adjusted substa-ntially as hereinbefore described and as indicated in Fig. 1 wherein the spark point, B12, is forced outwardly by means of the helical spring, B, iii frictional contactwith the terminal, B2, thus offering an easy path for the passage of the current. When, however, the operator desires to determine the operative condition of the circuit the point, B12, is retracted by means of thc manipulative button, B, so as to cause a park spa-ce, B15, as shown in F ig. 2. When sufiiciently retracted to give the desired amount of space the said button is rotated slightly to one side vso thatv the sto in, B7, last vwithdrawn through the notc i, 1, provided'in the flange on the casing, B4, as described, bears against the flange when `the button'is released, txh'us r s a result of this operation the current is forced to arcover thespace, B1", producing in its passage a visible spark in synchronism with the ignition spark emitted by within the engine.` This result )roves the operative condition of the circuit without requiring the removal of any part thereof. If, however, the electrical energybe nil or so feeble as to be unable-to force .a passage the ldefective condition of the circuit is at once observed by a weak or intermittent spark or by the entire absence thereof. When'employed on a multi-cylinder motor my device 'will enable the operator to locate instantly and without the removal of any part the rately Said clamp the sparlvplug' particular circuit in defect and whether such defect be in the generalcircuit system onin a ,particular cylinder. Furthermore,I 'the operator is enabled by these means to accuretiine the ignition'within the engine.

Having fully described my invention I claim as new and desire to secure by Letters Patent i 1. In a spark indicator, the combination with anv insulation base, of a stationary electrede and an adjustable electrode oppositely mounted on the base, said adjustable electro'de comprising an upwardly extending support, la sleeve or casingon said'support, a movable stem-member projected through the sleeve, and means' for keeping the stommember normally vin contact with the stationary electrode. I

2. In a spark indicator, the combination with an insulation base', of an adjustable electrodemounted on the -base and comprising an upwardly extending support, a sleeve or casing on said support, a movable stemmember projected through the sleeve and provided at one end with a coiitact-point and at the other end with means :for manipulating the stem-member.

3. Ina spark indicator, thecombination with an insulationbase, of oppositely'disposed electrodes mounted thereon, one of said electrodes comprising an upwardly extending support, a sleeve or casing on said support,.a rotatable stem-member projected through the sleeve and adapted to be norinally in contact with the other of said elecu trodes, and means for holding said rotatable member in a retracted position.

.4. In a spark indicator, an adjustabley electrode comprising a sleeve or casing provided at one end with an interior annular flange or edge having a notch therein, a slidable stein for projection through the sleeve, a plurality olspaced pins or stops provided laterally on'the stein within the sleeve and adapted to pass through the notch in said flange, .and means for retracting androtating the stem within the sleeve.

v5. In a spark indicator, the combination withan insulation base, of oppositely disposed electrodes mounted on the base, one of said electrodes comprising an upwardly eX-, tending support, a sleeve or casing on said' support, a'slidable stem-member projected through the sleeve, spring means within the sleeve tending to keep said stein-membernormally in contact with the other of said electrodes, and insulating means provided on said stem-member for manipulating the same. l

6. In a spark indicator, the combination with an insu-lation base, ofastationary ciectrede` and an adjustable electrode oppositely mounted en -said base, said base andstationary .electrode having means for-attachment and connection to a spark plug and said adjustable elect-rode having ametzil Standard l In testimony whereof I have affixed my carrying a metal casing or sleeve, a movable l signature, in presence of two Witnesses, this metal stem member projecting' through the l thirty-iirst day of July, A. D. 1907.

casing and means for keepingl the stem mem- FRANK W; RNER BRANDOY. ber normall5T in. Contact with the stationary l `Witnesses:

electrode, l:md means for makmg;` electrical g JOHN J. WHITTLESEY,

uonueotion to the standard. E WILLIAM E. BAGG. 

